1. Field of the Invention
This invention pertains to door actuating systems. In particular, this invention pertains to door actuating systems for slidingly opening and displacing door members. More in particular, this invention relates to door actuating systems utilizing frictional drives to open and close the door member. Still further, this invention pertains to door actuating systems which utilize motor drive elements coupled to frictional gripping members for opening the door member. More further, this invention relates to a counter-weight drive mechanism which is frictionally coupled to a drive bar and displaces the door member into a closed position upon deactuation of the motor. Additionally, this invention pertains to a door actuating system which relies upon frictional drive mechanisms to reverseably displace a door member.
2. Prior Art
Door actuating systems for opening and closing doors are known in the art. However, in some prior art door actuating systems, the door member is rotationally swung about a verticle axis. This has the effect of possibly impacting a person who is entering or leaving an enclosure. Thus, in such door systems, a person may be hurt when the door is unsuspectingly opened.
In some prior art door actuating systems, the door member is slidingly moved through use of a pneumatic or hydraulic type actuating device. Such systems are complex in hardware and provide for increased cost of manufacture. Additionally, in such prior actuating systems, due to the nature of hydraulic and/or pneumatic actuation, impact of persons entering or leaving an enclosure may result in the person being hurt. In general, in such prior door actuating systems, the door member does not yield to any great extent upon impact of a person and injury may thus result.
In prior hydraulic/pneumatic type door actuating systems, the actuating elements do not permit the user to open or close the door member when such prior art door actuating systems become jammed in an open or closed position. THus, in some prior art door actuating systems of this type, there is no manual over ride to allow opening or closing of the door member.